Improvement in electro-magnetic dental pluggers



UNITED STATES PATENT; OFFICE.

WILLIAM G. A. BON WILL, OF PHILADELPHIA, PENNSYLVANIA.

IMPROVEMENT IN ELECTRO-MAGNETIC DENTAL PLUGGERSI.

S pecitication forming part of Letters Patent N o. 170,045, datedNovember 16, 1875; application filed July 21, 1873.

To all whom it may concern y Be it known that I, WILLIAM G. A. BoN-WILL, of Philadelphia, Pennsylvania, have invented an ElectricalTooth-FillingInstrument, of which the following is a specification: y

My invention relates to improvements in dental instruments designed tobe operated by electricity, the objects of my improvements being torender the instrument compact, to adapt it to the hand of the operator,and to facilitate the securing and the removal of the operating-tool,and tov regulate the action of the mallet. These objects I attain byarranging the insulated coils A and A closely together, with the tool Bat one side of orbeneath the same, `and a guard, D, at the same side; byproviding the instrument with a guard or handle, D, by which it may beheld in a proper position for operation in either the right or lefthand, as shown in the plan View, Figure 2; by so combining the tool Bwith an adjustable beveled pin, b, that it can be readily removed 'andreplaced, and adjusted from and toward the mallet, as shown in thesection, Fig.3; and by certain improvements in the circuit breakers,fully described hereafter, whereby the instrument is rendered moredurable, and its operation much facilitated.

A succession of blows, more or less rapid, is imparted to the tool B,which is held against the lling by a mallet,'F, forn1ing'-tl1e armatureof a magnet inclosed within two adjacent coils, A and A', the circuitbeing completed at one point by the hand of the operator, and beingautomatically broken at another point by the mallet, which, whenattracted toward the magnet, and just before or at the. moment ofstriking the blow, breaks the circuit, and is then suddenly drawn backby its spring h, the circuit being automatically completed by aspring-lever, H, when the mallet will be again attracted and strikeanother blow, and will in like manner again break the circuit and springback, and so on as long as the operator completes the circuit at theopposite point.

The toolis placed at one side of or beneath the coils, which I arrangeclose together, as shown in the diagram, Fig. l, thus reducing the bulkl of the instrument considerably. The main object of this arrangement isto enable the operator to hold the tool in the same position as he wouldthe ordinary instruments, the guard D being arranged at one side of andbelow the tool, the rear end of which, therefore, rests .in the Vhollowbetween the thumb and torenger, the latter extending forward parallel'to the stem. By this means the automatic tool may be manipulated asreadily as the usual hand-tools. I also reduce the size of the coils andthe weight of the mallet, and yet obtain as sharp or a sharper blow withthe same battery 5 for the striking portion of the v mallet, owing tothe position ot the tool, is extended over the coils, which enables meto obtain a longer leverage, and to strike with the end instead of withthe side of the weighted portion of the mallet. (See Fig. 3.) Thislightness is also of advantage when soft blows in very quick successionare to be struck.

It' desired, the coils may be brought still closer together by attenin gtheir inner adjoining sides to a greater extent than is shown in thedrawing.

Another important feature of my present inven tion is the disposition ofthe frame E, handle E, guard D, and mallet F, in respect to the coilsand tool, the arrangement being such as to so lower the center ofgravity in the working position of the instrumentas to enable it to restsolidly upon the operators hand, as shown in Figs. 2 and 3. The hookedguard or handle D serves to determine the position of and to retain theinstrument in the hand, and much facilitates its operation, theindex-finger being passed through the same,ifthe instrument be held inthe right hand, as shown in 1 Fig. 2, while if it be held in the lefthand the thumb is passed through the said guard. The latter may be inthe form ot' a ring 5 but I prefer that it should be hooked. may also,if desired, be renderedadjustable upon the instrument.

lt will be observed that the handle E', instead of being provided withianges, as heretofore, is cylindrical, this also facilitating thegrasping and holding of the instrument by either hand.

The tool B is adapted to an opening in the handle E' and frame E,through which it can be freely passed, a spring stud or pin, b, yield-The said guard ing to permit its passage, and serving as a retainer forthe same, the said pin having an abrupt edge upon one side adapted to ashoulder, latter from bein g forced back'upon the mallet beyond theproper point, while the opposite edge of the said pin, which is adaptedto theshoulder a of the tool, is beveled, as shown in Fig. 3, so as toretain the said tool in position under ordinary circumstances, but sothat it will yield, and permit the withdrawal of the same by a slightei'ort. The pin b is secured to a plate, bf, rendered adjustable fromand toward the mallet upon the frame E, this adjustment of the plate andpiu ei'ecting also sufficient adjustment of the tool to take up theeii'ects of wear, and rendering any adjustment of the parts ot' themallet unnecessary, the latter being rigid 'and non adjustablethroughout. rlhe current passes from the stud t', through a spring, j,Fig. 4, to a slide, G, which the said spring has a constant tendency toforce in the direction of the arrow l, and from the said slide throughan adjustable screw, d, casing k, and spring c to a lever, H, the latterbeing maintained in contact with a screw, f, through which the currentpasses to the coils, by the said spring e.

A hard-rubber or other non-conducting projection, in, on the mallct actsdirectly upon the short arm ofthe lever H, when the mallct descends, andthus forces the same back from the screw j', and breaks the circuit.

The several parts are so arranged in respect to each other that thecircuit is not broken by the mallet until the latter has almost or quitestruck the blow, the full power of the mallct being thus obtained, andample time being afforded for its reco l before the circuit is againcompleted by the lever H.

One end ot' the spring e to which the lever H is connected, is woundupon a screw, n, by turning which the power of the said spring can beincreased or diminished, as desired, and consequently the rapidity ofthe recoil of the lever H, and the rapidity of the blows of the mallct,can be regulated by means of the said spring, as desired.

rllhe screw f is adj ustable, so' that the effects of wear can `bereadily taken up by means of the same, and the bearings, both of thelever H and the niallct,are also rendered adjustable for the samepurpose, and to prevent oxidization of the bearings of the lever thecurrent is not passed through the same, but dia, of the tool, and thuspreventing thel rectly to the long arm of the lever through the springe.

It will be observed, on reference to Fig. 4, that when the instrument isnot in use the Circuit is broken by the slide Gr, which is forced awayfrom the adjustable screw d by the spring j,- but in the act of forcingthe tool against a iilling or other object the pressure of theindex-finger or thumb upon the roughened portion of the Vsaid slidenaturally forces the same in the direction ofthe arrow, Fig. 2, and thuscompletes the circuit without special effort on the part of theoperator.

My improved instrument, although especially adapted for tooth-filling,can be applied in the arts generally, wherever power by electricity isneeded or can be used for actuating' a hammer.

I do not claim a magneto-electric dental instrument in which the ltoolis operated by a vibrating mallet, nor the combination with such aninstrument of an automatic circuitbreaker; but

I claim as my inventionl. An electric dental instrument, in which theinsulated coils A A are arranged close together, with the tool B betweenand at one side, and the guard D upon the same side, and extendingbeyond the tool, all as and for the purpose set forth.

- 2. The combination, with the instrument,

of a guard or handle, D, by which the said instrument may be held in aproper position for operation in either the right or left hand,substantially as herein described.

3. rEhe combination of the socket, open at both ends, the tool B fillingthe socket, and

having shoulders a a', and a spring-retaining pin beveled at one edge,as and for the purpurpose set forth.

4. The retaining-pin b, secured to and rendered adjustable upon theframe, with a plate, b', from and toward the mallct F, substantially asand for the purpose specied.

5. The combination, with the said lever H,

of a spring, e, the power of which can be in-k creased or diminished asrequired, and through which the current is caused to pass, as specitied.

In testimony whereof Ihave signed my name to this specification inthepresence of two subscribing Witnesses.

Witnesses: WM. G. A. BON WILL.

` WM. A. STEEL,

HARRY SMITH.

